6747 数字黑洞

#include<bits/stdc++.h>
#define f(i,s,e) for(int i = s; i <= e; i++)
#define ll long long
using namespace std;
const int N = 1e3+10,inf = 0x3f3f3f3f;

int main()
{
    int n,ans = 0; //ans次数
    cin >> n;
    while(n != 495)
    {
        int a = n % 10; //个位 
        int b = n / 10 % 10; //十位 
        int c = n / 100; //百位 
        if(a < b) swap(a,b); //swap：交换两个变量的值 
        if(a < c) swap(a,c);
        if(b < c) swap(b,c); //经过这三次swap，可以保证a > b > c 
        int maxx = a * 100 + b * 10 + c;
        int minn = c * 100 + b * 10 + a; 
        n = maxx - minn;
        ans++;
    } 
    cout << ans;
    return 0;
}